This invention relates to an ultrasonic diagnosis apparatus adapted to display a Doppler blood flow image on a display unit.
An ultrasonic diagnosis apparatus measuring the speed of blood flow in a living body is required to transmit ultrasonic pulses a plurality of times into the living body in the same direction, so as to measure a Doppler frequency shift of the reflected wave due to the blood flow and to display the result of measurement as a Doppler blood flow image. However, in a prior art ultrasonic diagnosis apparatus in which both the angle of scanning with an ultrasonic pulse beam and the region of Doppler blood flow image display on a display unit are fixed, the frame rate of a Doppler blood flow image is only about 1/n (n: a positive integer less than ten) of that of a B-mode image when a scanning area for the Doppler blood flow image and that for the B-mode image are the same, and the rate of appearance of flickering is higher in the former image than the latter image. Further, due to the fact that the direction of transmission of the ultrasonic pulse beam transmitted from an ultrasonic probe for the measurement of the Doppler blood flow image is fixed relative to the ultrasonic probe in the prior art ultrasonic diagnosis apparatus, there has been a problem that those having a considerable skill in this kind of measurement can only determine the position and direction of the ultrasonic probe relative to a living body or an object to be diagnosed.